Plasma-Chemical and Reactive Ion Etching of Gallium Arsenide in Difluorodichloromethane with Helium

The kinetics of the interaction of high-frequency plasma of difluorodichloromethane and its mixture with helium with the surface of gallium arsenide (GaAs) is experimentally studied. It is established that in the studied range of conditions, the original difluorodichloromethane molecule completely decomposed into atomic carbon. It is confirmed that the main chemically active particles responsible for etching are reactive chlorine atoms. It is shown that the etching process occurs in the mode of an ion-stimulated chemical reaction, where the desorption of products under the influence of ion bombardment plays a significant role in cleaning the surface. The emission spectra of plasma radiation in the presence of a GaAs semiconductor wafer are analyzed. The control lines and bands are selected to control the rate of the etching process based on the emission intensity of the lines and bands of the etching products.